is 2 1978201 - 1
has 595498 decimal digits
takes 0.130 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26715.020768.6567 %500000150000000.12305.1163 %15.143770.2603 %
Target2620.310666.1290 %80005000000.00331.1970 %0.313966.5345 %
Difference+5+14.7101+2.5277 %+492000+14500000+0.1197+3.9194%+14.8298+3.7259 %

Known prime factors (2 factors, 117.8 bits, 0.00595351% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
1978201258590434731134.5906536
23 × 19 × 43
-19431.637e-91.936e-63.687e-6
1978201109744908744921074940756172683.1822773856366085172208
24 × 292 × 47 × 467 × 929 × 10109683
2015-10-11929101096831,352,0700.05260.0981

1 Composite Factors:
P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2015-10-11alpertronManual testing500000150000001222683.1820.1238.175%


Trial Factoring results:
5758596061626364656667
No TF results for M1978201


ECM factoring results:
Total ECM effort:25.689 GHz-days
Estimated T-Level:25.329
DigitsB1CompleteFacMiss
201100010.9130.002%
25500001.03135.679%
302500000.06693.639%
3510000000.00399.691%


ECM Summary

B1B2factorcurvesGHz-days
500005000000271.956
50000665000070.688
50000675000070.557
50000687727870.562
50000750000021621.93


Lucas-Lehmer results:
No L-L results for M1978201


PRP results:
dateuseridcompidcofactorsres64
2017-09-30alpertronManual testing
25859043473
10974490874492107494075617
627C68233E8D7AD3
2017-10-20Oliver KruseThreadripper-PC
25859043473
10974490874492107494075617
627C68233E8D7AD3


CERT results:
No CERT results for M1978201


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
100
101
102
103
104
105
106
100
101
102
103
104
105
106
107
108
TF factor-bounds graph:
this exponent TF target: 62
TF double-checked to: 67
ECM T-Level=25.33 ~= 68-bit
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290
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Last modified: 2024-03-13T02:15:48+00:00